Coiling cord



H. M. HAY

COILING CORD June l, 1937.

Filed Dec. 2l, 1929 C5 Sheets-Sheet l H. M. HAY

COILING CORD `lune 1, 1937.

, 1929v 3 sheets-sheet 2 Filed. Deo

A l In June 1, 1937'. H M HAY 2,081,928

COILING CORD Filed Dec. 2l, 1929 3 Sheets-Sheet 3 hr1/egg Patented June 1, 19737V UNITED sTarss PATENT orrlcl:

COILING CORD Howard lVI. Hay, Wenonah, N. J.

Application December 21, 1929, Serial No. 415,634

6 Claims. (Cl. 173-367) My invention is designed to provide improved ers partly or Wholly around the cords, and in means for coiling cords to prevent the entangleeach type of application I provide a plurality ment and breakage thereof and the disturbance of relatively short spring sections connected toof papers or other objects thereby. It is appligether by members extending transversely relacable primarily to electric cords, such as are tively thereto and forming a coiler combined 5 used in connection with telephones, electric with an anchorage for non-rotatably securing a irons, or other portable apparatus utilizing elecportion of the coiler. Should the anchorage of tric current, and the coiling device may be the coller be unnecessary for certain purposes, utilized as a portion of an electric circuit or may the sheathing of all or a portion of the coiler 10 be electrically insulated therefrom. having offset individual spring sections and the 10 In a preferred embodiment of my invention, provision of a cylindrical housing or collar at the cord is coiled by a helical spring preferably one or both ends thereof provides a more efflhoused Within the cord covering or sheath Which cient, as Well as` more economical and presentconceals and insulates the coiling device. The able device than has been hitherto available.

coiler is preferably composed of a plurality of The characteristic features and advantages of 15 relatively short elastic sections connected tomy improvements will further appear from the gether by spring members extending transversely following description and the accompanying thereto, so that the torsional stresses resulting drawings of illustrative embodiments of my imfrom the uncoiling of the heliX by an axial pull provements.

thereon is taken up by flexing the members lon- In the drawings, Fig. 1 illustrates the appli- 20 gitudinally at the bends thereof instead of by cation of my invention to the mounting cord of disrupting the mOlBClllai arrangement of the a usual desk set type of telephone instrument wire metal by rotation of the Wire metal on the having a transmitter stand normally held or axis of the Wire, such as commonly occurs when moved by the user and a receiver Connected a helix S UDWOUII- by 2i pull thereol- The 1101- therewith by a relatively short cord; Fig. 2 25 sional Stresses resulting from the unwinding oi shows the instrument illustrated in Fig. 1 with the helix are moreover preferably distributed the coiled mounting cord partly elongated; Fig. thrOughOut the length of the Collins device by 3 is a perspective view illustrating the applicaanchoring One 0T both ends thereof against rotion of my improvements to a continental or tation, and one or both ends of the Coller may hand set type telephone having the transmitter 30 be projected through and Wound around the and receiver mounted upon a hand piece consheath to provide a sleeve or housing preventing neeted by a relatively long cord with a base or sharp bends of the conductors or abrasion of stand which is normally not held by the user, the sheath. My improvements. conduce to the but may be connected with the terminal block life and elasticity of the coiling device as well as or bell box by a mounting cord similar to that of the Cord, and avoid twisting of the oord shown in Fig. 1 or by an uncoiled cord; Fig. 4 is which has heretofore resulted in deterioration an enlarged View of a straightened section of and breakage of the cords when used with coilcord embodying one form of my improvements ing devices. and having the covering sheath partly removed It is not, of course, necessary that all of the to show the interior construction; Fig. 5 is` a 40 features of my invention be incorporated in part sectional peripheral View of a detached coil every embodiment thereof, as the advantages of having a preferred form of coiling means, the the separate characteristic structural features provision of fulcrum` points by the cord sheath may be separately used, although they are prefthreads for the several sections of the coiling erably all utilized Where the cord and its coilspring being diagrammatically indicated; Fig.

ing device are designed for arduous service. 5A is a part sectional axial view of a coil similar Features of my improvements are applicable to that shown in Fig. 5, but With the offset porboth to Wholly or partly sheathed coilers and to tions of the coller bent at right angles to their coller attachments applied exteriorly to cords, position in Fig. 5, and the action of the cord as, for instance, by bending members of the coilsheath threads in forming fulcrums for the 50 spring sections being diagrammatically indicated; Fig. 6 is a part sectional View of a straightened section of a cord provided with coiler having a modified form of bend, the engagement of the cord sheath threads to form fulcrums for the coiler sections being diagrammatically illustrated; Fig. 'i is a detached View of a form of anchorage for positioning the mounting cord coiler relative to a base or stand of an instrument such as a telephone; Fig. 7A shows the anchorage illustrated in Fig. 7 clamped to a stand and clamping a cord; Fig. 8 is a view similar to Fig. 7A but having the coiler projected through the cord sheath and forming a cylindrical cord housing engaged by the clamp; Fig. 9 is an enlarged view illustrating the an chorage of a coiler to the stand of a continental type phone; Fig. 10 shows a. modified form of anchorage for supporting the coilei1 upon the base of an instrument such as a continental type telephone; Fig. l1 is` an enlarged View illustratinga modified form of anchorage by which the coi-ler may be attached to and supported by the hand piece of a continental type telephone; Fig. 12 illustrates diagrammatically how the torsion resulting from pulling on a helix is converted into normal bending movements adjacent to the fulcrum sections of the offset wire sections of coilers embodying my improvements; Fig. 13 illustrates diagrammatically how the pulling a helix imposes torsional stress upon a straight wire about the axis thereof tending to disrupt the molecules; and Fig. 14 is a fragmentary view of a straightened coiler section having its members connected by multiple bends.

In the preferred embodiment of my invention, an electric cord, preferably composed of a plurality of relatively insulated strands, has housed within the braided sheathing thereof a coiling device consisting of a helically coiled spring having sections offset from one another and united preferably by reverse bonds or curves normally lying substantially in a plane common to the sections united thereby.

As illustrated in Figs. 4 and 5, the insulated conductors i, 2 and 3 have braided thereto by the sheathing 4 a coiler 5 consisting of spring wire bent in the form of a helix and having relatively ofset sections 6 and 6 united to one another by fulcrum forming members 1 connected with the members E and 6 by bends or curves 8 and 3. The coiling device 5 is electrically insulated from the conductors l, 2 and 3 by the insulation thereon, and may, if desired, be utilized as a portion of an electric circuit, as for instance a ground wire. The braiding of the sheathing about the strands and coiler forms a composite cord in which the members 'I are anchored by the sheath threads and act as though fulcrumed at substantially the points 9, so that pull upon the cord in the direction of the axis of the helix distributes the bending substantially throughout the length of the coiling device. By securing the bending of each of the individual f sections 6 and 6 relative to the points 9 the fatiguing oi any portion of the wire is avoided and the coiler returns to its initial helical form.

It is of primary importance in ceiling devices to avoid fatigue or permanent set of the wire, which quickly occurs where the helical coil is formed of straight wire. Where the helical spring is provided with offset portions necessitating in their formation an axial, as Well as a bending, twist of the wire, there is a tendency to fracture due to the shearing effect resulting from accentuating the axial twist or to bending transversely the wire section containing such axial twist. It, however, the offsets in the wire are provided by bends or loops made in the direction of the grain of the metal and without setting up torsional strains therein by axial twists, the stresses resulting from the straightening of the helix are so distributed that the coil has great durability and will return to its original condition even after many elongations.

While it is ordinarily preferable to use a complete reverse loop lying parallel to the plane of the periphery of the. helically coiled cord, the coiler may, if desired, be bent, as illustrated in Fig. 5A, with offset portions 6a and 6b at right angles to the position occupied thereby in Fig. 5 and lying substantially normal to the axis of the helix. In such form, as illustrated in Fig. 5A, the fulcrum forming section la is united to the offset sections 6a and 6b by the loops 8o and 8b, which are bent in accordance with the grain of the wire, and the sections 6d and Sb are disposed at different distances from the axis of the helix.

Where less elasticity and durability are re quired than are provided by complete reverse bends, such as illustrated in Figs. 5 and 5A, the wire may be bent, as illustrated in Fig. 6, to form oflset sections 6c and 6d connected by the. angularly disposed sections 'Ib by curved sections 8c and Bd, so as to give to the wire a saw tooth outline. The wires so bent may be coiled into the form of a helix with the teeth projecting either radially or axially.

It will be understood that when the coilers illustrated in Figs. 5, 5A and G, are incorporated in a cord, the members 1, 'lo and l'b function as fulcrums for the offset sections S, 6', or 5u, 6b or 6c, 5d respectively, so that bending resulting from an axial pull on the helix is distributed throughout the cord. The torsional action resulting from axial pull on the helix is converted into bending movements in the line of the grain of the Wire and primarily in the sections l, la

and 'Ib and the bends connecting them with the members 6, 6', or 6a, 6b, or 6c, 6d respectively, with consequent avoidance of any substantial torsional stress on the wire or twisting of the wire on the axis thereof.

The difference between the molecular action of a coiler embodying my improvements and of a coiler formed of straight wire is indicated graphically in Figs. 12 and 13. As illustrated in Fig. 12, when a coil such as illustrated in Fig. 5

is pulled axially, the members G and 6 rock relatively to one another on a fulcrum point in the section 1, and the torsional. effect is taken up primarily by the bending oi such sections 'l and the curves 8, B connected therewith. Since the bending is widely distributed and does not involve molecular displacement resulting from twisting of the wire on its own axis, the coiler is not fatigued and will recoil to its original shape indefinitely. On the other hand, when a helically coiled straight wire is pulled, the elongation of the helix results in imposing a complete axial twist in the wire for each loop of the helix pulled out, as indicated by the longitudinal lines in Fig. 13. Such torsional strain weakens and fatigues the Wire and results in the ready fracture thereof or a permanent set preventing restoration to the original helical iorm.

When a cord having a fixed anchorage is provided with a coiler, there is a tendency to concentrate the axial or torsional twist resulting from the straightening of the helix in the portion of the cord between its anchorage and the end of the coiler. In accordance with my invention, this difculty is overcome by anchoring the coiler at one or both ends thereof, thereby not only preventing twisting and deterioration of the cord, but also providing a support by which the cord is maintained out of Contact with the surface upon which the portable device associated therewith is supported.

As illustrated in Figs. 1, 2 and 7A, the stand I of a desk type telephone instrument has fixed thereto a bracket II providing clamping jaws I2 non-rotatably engaging the mounting cord having therein a coiling device, so that the coiled cord is supported clear of the surface I4 on which the telephone stand rests. When the instrument is moved, the expanded helix is disposed sufiiciently above the instrument supporting surface to avoid frictional contact therewith or disturbance of papers or the like thereon.

As illustrated in Figs. 1 and 2, the unanchored end of the coiler opposite the bracket I2 may be projected through the cord sheath and wound into a cylindrical housing 5 for the cord to prevent sharp bending of the cord at the junction between the coiled and uncoiled portions thereof. The maintenance of the coiled cord at an elevation above the base also avoids the tendency to kink the cord resulting from a complete rotation of the instrument on its vertical axis, since such rotation results in visibly wrapping the coil around the instrument and thereby directs attention to the improper manipulation thereof.

As illustrated in Fig. 8, the end of the coiler to be clamped also may be brought out through the cord sheath, wound in a cylindrical coil or housing 5 on the exterior of the cord and nonrotatably engaged in the clamp I2, thereby avoiding any wear on the cord sheath due to the pressure of the clamp as well as preventing sharp bending adjacent to the anchorage.

As illustrated in Fig. 9, the end 5a of a coiler encased within a cord may be projected from the end thereof and bent backward and fixed to a clip on the metal collar I5 encircling the end of the cord, which metal collar is non-rotatably secured to the bracket IB in the base of the telephone instrument. Such attachment may be made by means of a hook I'I or in any other suitable manner.

As illustrated in Fig. 10, the end 5b of the coiler may be projected through the sheath of the cord and bent into a loop I8 and looped around the neck of the standard of the telephone stand and latched by means of a hook I9.

As illustrated in Figs. 3 and 1l, the coiler has its end 5c projected from the end of the cord and bent back thereon into engagement with a clip or loop on the metal collar E@ encircling the cord and such collar is non-rotatably secured to the hand piece 2I by means of a screw 22 or in any other suitable manner.

It will, of course, be understood that the various anchorages illustrated may be used in conjunction with or separately from one another, and that many othermeans for non-rotatably supporting the coiler may be utilized, depending upon the character of the apparatus with which the cord and coiler are used.

When the cord 23 of the handpiece of the telephone is provided with a coiler, as illustrated in Fig. 3, it is frequently desirable to retard the pull exerted on the base 24 from lifting the handpiece 25 by providing a mounting cord 26 with a coiler wound into a helical loop 21 but having a straight section 28 between the helical winding and the base of the instrument. The two coil sections of the cords are thereby maintained sufficiently apart to prevent entanglement with one another and the resistance to unwinding by the helix 2'! checks the movement of the base 24 across the surface I4 when the helical section of the cord 23 is unwound in using the handpiece 25.

There are many Uses for my improvements aside from the application thereof to telephone cords, and when the coiler is subjected to heavy duty by embodiment in a heavy cord it is sometimes desirable to provide a plurality of members between the offset sections, as illustrated in Figure 14. In such constructions, the offset portions te and Gf are connected to one another by means of the fulcrum-forming sections le, 'If and lg which are united to offset sections and to one another by the bends or loops 8e, 8f, 8g and 8h.

As used herein, the term helix or helical spring is to be understood as to referring not only to the curve formed on a cylinder by a right line in a plane that is wrapped around the cylinder, as an ordinary screwthread, but also to a line formed by a point that moves around an axis while continuously receding from or approaching it, such as the shape of an ordinary watch spring, and to comprehend any type of coiled spring.

Having described my invention, I claimt- 1. A cord coiler comprising a coiled spring having sections connected with one another by substantially S-shaped bends.

2. A cord coiler comprising a coiled spring having a plurality of relatively straight sections overlapping one another at the ends thereof and bent members connecting the overlapped ends of adjacent sections.

3. The combination with an electric conductor and a sheath therefor, of a coiling wire housed within said sheath and normally lying in juxtaposed circumvolutions, each of said circumvolutions containing a plurality of sinuous bends each making a turn of approximately 180 degrees within a distance transverse to the axis of the sheath materially less than the inner diameter of the sheath of the cord, said circumvolutions being separable from one another upon pulling the ends of said conductor and the separation of such circumvolutions flexing the coiler at the sinuous bends in each circumvolution and thereby minimizing the application of torque to said wire about its own axis.

4. The combination with a plurality of electric conductors and a sheath housing all of said conductors, of a coiling wire housed within said sheath and normally lying in juxtaposed circumvolutions, each of said circumvolutions containing a plurality of sinuous bends each making a turn of approximately 18() degrees within a distance transverse to the axis of the sheath materially less than the inner diameter of the sheath of the cord and a substantially cylindrical collar encircling said conductors, an end of said wire being connected with and anchored by said collar.

5. The combination with a plurality of insulated conductors arranged in parallel, a sheath housing said conductors, of a coiling wire lying between said parallel conductors and housed within said sheath, said coiling wire normally lying in juxtaposed circumvolutions, each of said circumvolutions containing a plurality of sinuous bends each making a turn of approximately 180 degrees withcord of a circumvoluting coiler therefor, and means for securing the ends of said coiler to said cord and comprising a collar having a recess for the reception of the end of said coiler said recess being formed by an integral bight of said collar, and said coiler passing with said cord through said collar and having an end bent backward over the outer surface of such collar and engaged in said recess by said bight.

HOWARD M. HAY. 

